The goal of the proposed research is to determine the general applicability of a newly proposed model of thermal adaptation in biological membranes. The goal of the proposed research is to determine the adaptive significance to conserving the dynamic phase behavior (i.e., the ability of membrane lipids to undergo local rearrangements necessary for fusion, budding, cell division and intracellular membrane vesicle trafficking) of membrane lipids in multicellular or poikilothermic animals. The predictions of this dynamic phase behavior model will be tested in various membrane fractions from temperature-acclimated fish adapted to both cold and warm water and, in selected experiments, rat. The significance of the proposed work lies in better understanding how membrane lipids influence membrane function and has implications for both disease processes that are membrane based as well as the impact of global warming on natural populations.
